Public health experts recommend that HIV positive women in resource-limited countries should breastfeed their babies. Women in industrialized countries who are on effective antiretroviral therapy (ART) and have undetectable viral load should also be advised that breastfeeding may be an acceptable option, according to an opinion piece by Pamela Morrison, an international board-certified lactation consultant, and colleagues in the August 5, 2011, advance online edition of AIDS.

After a report of HIV transmission through breast milk in 1985, the U.S. Centers for Disease Control and Prevention (CDC) recommended that HIV positive mothers in the U.S. should not breastfeed. Similar guidelines have been in effect in Europe and other industrialized areas.

In resource-limited countries in contrast -- due to greater risks associated with unclean water for formula and inadequate nutrition -- the World Health Organization (WHO) and other public health authorities recommend that women with HIV should breastfeed exclusively for 6 months if replacement feeding is not "acceptable, feasible, affordable, sustainable, and safe."

'By mid-2011 at least 8 studies demonstrated that early and appropriate ART combined with exclusive breastfeeding for up to 6 months reduces the postnatal transmission risk to 0%-1.2%,' Morrison and colleagues note. 'In a recent, large study with extensive follow-up, no cases of postnatal transmission occurred among women adherent to ART.'

The Mma Bana study in Botswana showed that HIV positive mothers who receive combination ART during pregnancy and while breastfeeding have only about a 1% likelihood of transmitted the virus to their babies, and no transmissions during breastfeeding occurred among women taking a modern multi-class regimen.

HIV positive pregnant women in industrialized countries are more likely than those in resource-limited settings to receive state-of-the-art treatment that keeps their viral load below the limit of detection. Under these circumstances, HIV transmission during pregnancy has been shown to be exceedingly rare.

As reported at the recent International AIDS Society conference in Rome, the HPTN 052 study showed that sexual transmission is also very rare within discordant couples if the positive partner is on effective ART with undetectable viral load. There is every reason to believe that HIV transmission during breastfeeding would be similarly rare when the mother has fully suppressed virus on ART.

Furthermore, a growing body of evidence indicates that infants benefit from breastfeeding in many ways, even if high-quality replacement feeding is available. "While the assumption that artificial feeding from birth is without risk in [industrialized countries] is still common," the opinion authors write, "research has begun to call this belief into question."

"In the USA, conservative estimates of excess mortality due to suboptimal breastfeeding vary from 911 to 720 deaths per year, with approximately 400 being due to diarrhea alone," they continue. "Artificial feeding increases the risk of necrotizing enterocolitis and death among premature infants and increases the risk for sudden infant death syndrome."

Morrison and colleagues review the pressure on HIV positive women in developed countries to not breastfeed -- up to and including legal sanctions. At least 1 mother has lost custody of her child until she agreed to formula-feed.

But women with HIV are increasingly expressing their desire to breastfeed, given the growing evidence of the low risk of transmission when viral load is well controlled on ART. In the U.K., this is especially the case among immigrant women from Africa and other regions where breastfeeding is the cultural norm and there is strong family and peer pressure to breastfeed and stigma associated with replacement feeding, the authors explain.

In view of these concerns, the British HIV Association (BHIVA) and the Children’s HIV Association recently held a consultation to revisit infant feeding guidelines for HIV positive mothers in Britain. While the guidance still recommends formula-feeding for most HIV positive women, it also recognizes that a mother on effective triple-combination ART with repeated undetectable viral load at the time of delivery may -- after careful consideration -- choose to exclusively breastfeed her baby for the first 6 months. During this time the woman should receive frequent follow-up, viral load monitoring, and support for medication adherence.

"[W]e would argue that data lacking when [industrialized country] policies on HIV and infant feeding were formulated in the 1980s concerning (1) the extremely low risk of postnatal HIV transmission for women receiving appropriate ART with resulting undetectable viremia, (2) the safety and feasibility of heat treatment of expressed breastmilk and (3) the mortality risk of breastfeeding avoidance in [industrialize countries] argue for a rethinking of HIV and infant feeding policies in other [industrialize country]," Morrison and colleagues conclude. "Following the British precedent, when appropriate preconditions exist, HIV-infected women should be supported in making informed infant feeding choices."